Emergent lines of research and theory suggest the importance of considering the contributions of social and non-social attentional cues for language acquisition and performance. However, in the current literature, these contributions have been examined separately. The overall aim of the current application is to systematically examine whether infants' early visual attention (to social and non-social targets) predicts their joint attention, and whether the co-development of both together predicts the emergence of language. Two specific aims (which correspond to the K99 and R00 phases) are intended to address current gaps in our knowledge. The first aim (K99) will test the hypothesis that social attention differentiates from general attentional processes during the first year of life. To date, it is unknown whether attention regulation skills differ in the context of social and non-social input across development and how these skills map on to joint attention behaviors. Joint attention may reflect development of general aspects of attention, or alternatively, it may reflect socially specific attention (i.e., attention regulation in the context of other social agents). The second am (ROO) will test the hypothesis that across the first two postnatal years, visual attention and join attention will make independent and unique contributions to language outcomes. Although basic measures of visual attention and measures of joint attention have been independently associated with language outcomes, their relative contributions across development have not been systematically examined. Our recent work suggests visual attention and joint attention account for unique variance in language variability in the second year of life. The initial period f the award (K99) will involve a systematic cross-sectional study mapping the associations between early attentional processes and joint attention at 8, 10 and 12 months of age. This phase will allow mentored research training in processing raw heart rate data (with Dr. Colombo), child language (with Dr. Brady), advanced statistics and large-scale longitudinal experience. The independent phase of the award (R00) will build on these results in a large-scale longitudinal study that includes these same measures (at 8, 10 and 12 months of age) and incorporates measures of language outcome into the second year of life (14 and 18 months of age), with the ultimate aim of testing hypotheses about the developmental trajectories of visual attention and joint attention in prediction of language emergence. The aim of this application is to develop an independent and active research program that examines these skills with much greater granularity, both in terms of developmental course and biobehavioral measurement. The Pathways to Independence award would allow me to integrate new research skills with my enduring interests in attention and language in a series of programmatic studies that would both contribute to the scientific knowledge base and further develop my role in the field as independent developmental scientist.